source rock
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Petroleum originates in fine-grained sedimentary rocks, known as source rocks. Within these rocks, organic material called kerogen is subjected to increasing temperatures and pressures due to deeper burial by accumulating sediments.123
This process, occurring within the "oil window" at depths of roughly 760 to 4,880 meters (2,500 to 16,000 feet) and temperatures between 65°C and 150°C (150°F and 300°F), causes thermal degradation and cracking of the kerogen. This releases hydrocarbons, which then migrate from the source rock into more porous reservoir rocks where petroleum accumulates. The characteristics of crude oil can change based on the age and geothermal gradient of the source rock.31
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petroleumFrom kerogen to petroleum: the mature stage…the oil window of a source rock over long periods of time results in the cracking of the kerogen molecules and the release of the attached paraffin chains. Further heating, perhaps assisted by the catalytic effect of clay minerals in the source rock matrix, may then produce soluble bitumen compounds,…
Read More…the oil window of a source rock over long periods of time results in the cracking of the kerogen molecules and the release of the attached paraffin chains. Further heating, perhaps assisted by the catalytic effect of clay minerals in the source rock matrix, may then produce soluble bitumen compounds,…
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natural gasOrganic formation processThus, all source rocks have the potential for gas generation. Many of the source rocks for significant gas deposits appear to be associated with the worldwide occurrence of coal dated to Carboniferous and Early Permian times (roughly 358.9 million to 273 million years ago).
Read MoreThus, all source rocks have the potential for gas generation. Many of the source rocks for significant gas deposits appear to be associated with the worldwide occurrence of coal dated to Carboniferous and Early Permian times (roughly 358.9 million to 273 million years ago).
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sedimentary rockOil and natural gas…oil are generated from such source rocks only after heating and compaction. Typical petroleum formation (maturation) temperatures do not exceed 100 °C, meaning that the depth of burial of source rocks cannot be greater than a few kilometres. After their formation, oil and natural gas migrate from source rocks to…
Read More…oil are generated from such source rocks only after heating and compaction. Typical petroleum formation (maturation) temperatures do not exceed 100 °C, meaning that the depth of burial of source rocks cannot be greater than a few kilometres. After their formation, oil and natural gas migrate from source rocks to…
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